Insects

stemweevil blackbeetle blackbeetlelarvae blackcricket
Argentine Stem weevil Black Beetle Black Beetle Larvae Black Cricket
grassgrub largeporina sodwebworm tasmaniangrassgrub
Grass Grub Large Porina Sod Webworm Tasmanian Grass Grub



Argentine Stem Weevil

top of page

Argentine Stem Weevil Listronotus bonariensis like other weevils are distinguishable from beetles by their long snouts and their legless grubs or larvae. Adults are small being approximately 5-10mm long and greyish brown in colour whilst the larvae are creamy white. This is mainly a pest of ryegrass in particular with the larvae feeding within the grass stem whilst the adults feed on expanded leaves. The damage caused by adults in particular is noticeable by the windows they chew in the leaves. Damage from Argentine Stem Weevil can occur throughout the warmer months from September through until late April.




Black Beetle

top of page

Heteronuchus arator. The adults of this species can be observed throughout the year but are generally observed from March until October. The grubs live in the top 50mm of the soil and eat the roots of grass plants. Often the first sign of damage is seen as areas of the lawn dying during dry weather conditions. Because the grubs eat the roots the plants are less able to gain sufficient moisture to meet their requirements. The adults themselves do little or no harm to the plants. The grubs are larger than grass grub (10 - 20mm) and are creamy white with a black head and abdomen.


Solution

Survey the lawn by take spade width squares in a variety of area preferably before damage is noticeable. This is best to occur in November or December. Tip the sod upside down and inspect the soil. If two or more grubs are found then apply Pyrifos G granules at label rates. Please treat this compound as a poison and take all necessary precautions to ensure that there is no skin contact.




Black Beetle Larvae

top of page

No information currently.




Black Cricket

top of page

These are also known as Black Field Crickets or simply field crickets. They are generally found on clay soil types over summer when cracks in the ground profile create an ideal environment for them to live. The crickets live in these cracks or holes in the ground and emerge to feed on the leaves of the grasses often severing leaves and taking them back to their burrow to eat. They take the closest plants first and as a result a bare patch around their home is very evident. The majority of the damage is visible over the summer months from January until April. They are visible during the day and move quickly when disturbed by foot traffic.


Solution

Increase the watering regime to swell the soil and decrease the incidence of cracks on the soil surface.
Apply bait. This is normally in the form of treated wheat or barley. Care should be taken as the bait is poisonous.




Grass Grub

top of page

Costelytra zealandica also known as Grass Grub or Brown Beetle is a native species that like many biting and chewing insect has an annual life cycle. The adults emerge from October through until February and lay eggs in the soil. They feed on foliage and may occasionally strip the leaves of cherry and plum trees. The grubs that develop from the eggs live in the root zone from March until July eating the roots of susceptible species. This reduces the plants ability to uptake water and the outcome is patches of dead grass particularly through times of drought or sustained moisture stress. The grubs vary in size from 10 ? 15mm in length and are creamy white colouration with a black abdomen. Flocks of birds particularly starlings feeding in turf often indicate a heavy infestation of grass grub.


Solution

Survey the lawn by take spade width squares in a variety of area preferably before damage is noticeable. This is best to occur in November or December. Tip the sod upside down and inspect the soil. If two or more grubs are found then apply Pyrifos G granules at label rates. Please treat this compound as a poison and take all necessary precautions to ensure that there is no skin contact.




Large Porina

top of page

Wiseana spp. Porina comprises several species of native moth whose caterpillars are common pest of turf. These large caterpillars are approximately 50 - 75mm long when mature and are grey to greyish yellow in colouration. They live in shallow vertical tunnels and emerge at night to feed on grass leaves. Turf damage around the tunnels is particularly noticeable from autumn onwards.


Solution

Place boards on the lawn over an evening. Once the boards are removed the following morning the porina burrows will have been clearly exposed. If five (5) or more burrows are apparent per square metre then control will be necessary.




Sod Webworm

top of page

This is made up of the species that includes Eudonia spp., Orocrambus spp. and Scoparia spp. The adults emerge as moths from September through until December. The resultant caterpillars live in shallow burrows in the ground and emerge to eat the foliage. The caterpillars range from 10 - 20mm in size and are generally green with dark green spots located in lines down the length of the body. Damage from Sod Webworm is prevalent form January through until June.




Tasmanian Grass Grub

top of page

Acrossidius tasmaniae. This species is often confused with Black Beetle as both the adults and the grubs look similar. However, the grubs which unlike Black Beetle live in small burrows near the surface and emerge to eat foliage near the tunnel entrance. This creates damage from the period May through until November, with the adults emerging in December and January.


Solution

Survey the lawn by taking spade width squares in a variety of areas preferably before damage is noticeable. This is best to occur in November or December. Tip the sod upside down and inspect the soil. If two or more grubs are found then apply Pyrifos G granules at label rates. Please treat this compound as a poison and take all necessary precautions to ensure that there is no skin contact.